The popstar, who split from Elen Rivas last month, said that he rates himself as a "seven" when he's looking his best.
Asked to rate his attractiveness on a scale of one to ten, he told Heat: "Less than it was. About a seven on a good day, six on a bad day.
"I don't think I ever look really horrible, but I am noticing a few lines here and there.
"I'm Mediterranean, tanned and not as good as I was."
Despite his complaints, the 37-year-old revealed that he has no qualms about showing off his body.
He explained: "Have I ever been skinny dipping? Yes, many times. The last time was at home in Cyprus. I've done it jumping off cliffs."
The 'Behind Closed Doors' singer also confessed that he likes to go out without wearing underwear.
Asked about his underwear, he responded: "I'm not wearing any at the moment - I went freeflow today."
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Watch Peter Andre talk about the future of his reality show Peter Andre: The Next Chapter below: